Process of reclaiming sludge acid in petroleum refining



Feb. 9, 1932. O MANT|U$ 1,844,513

PROCESS OF RECLAIMING SLUDGE ACID IN PETROLEUM REFINING Filed July 7. 1930 OOOOOOOOO oococc INVEN TOR.

A TTORNEY.

Q6 out No.

Patented Feb. 9, 1932 OTTO MANTIUS, OF NEW YORK, N. Y.

PROCESS OF RECLAIMING SLUDGE ACID IN PETROLEUM REFINING Application filed July 7,

This invention is a process for reclaiming sludge acid in petroleum refining and is more particularly directed to improvements in the process described and claimed in Pat- 1,38%978, issued July 19, 1921 to l valter Simonson and Otto Mantius.

In the refining of petroleum, the oil, after being treated by sulphuric acid in an agitator, is separated is so far as practically feasibleby stratification, leaving a residue generally known as sludge. This sludge is treated with hot water or steam and permitt-ed to stratify. The oil is then drawn off leaving what is known to the art as sludge acid. This sludge acid is contaminated with tar, oil and water, and other impurities.

The process of said patent relates to the treatment of this sludge acid for the purpose of recovering the acid for reuse in the refinement of petroleum. According to that process, the sludge acid is placed in a vacuum concentrator wherein it is concentrated by heat from internal steam coils. After concentration, the acid and the carbonaceous matter which it contains, are separated by decantation to remove the latter, leaving reclaimed concentrated acid which may be iuixedqwith fuming sulphuric acid for re-use.

Experience with certain oils, however, has shown that during concentration treatment, as stated, there is a point in the operation wherein the degree of concentration of the acid together with the heat from the coils brings about decomposition of certain residual organic compounds, such, for example, as naphthenic and sulphonic acids, causing a violent evolution and consequent foaming which makes it impossible to uninterruptedly continue to concentrate such acids in the vacuum concentrator.

It has thus been heretofore found necessary in such cases to carry the concentration of the acid in the evaporator only to approximately the foaming point and to thereupon remove the material from the concent ator and subject it to a collateral or inclependent treatment in separate open tanks or vessels. The t 'ansfer of the sludge acid from the concentrator to a separate vessel and its subsequent treatment therein, has heretofore 1930. Serial No. 465,884.

invariably been accompanied by release into the atmosphere of fumes "and vaporsvvhich by the addition of certain novel procedure,

sludge acid of the character under consideration may be subjected tocomplete concentration treatment within the vacuum concentrzu tor, so that when they are finally discharged from the concentrator, they may be passed directly into a suitable container in finished concentrated condition. Another object of the invention is to provide a process of the character referred to wherein the fumes and vaporsaredisposed of without release thereof into the atmos phere.

Thus according to the present invention, the sludge acid in relatively weak condition enters the vacuum concentrator as in the said prior process and is thereupon concentrated until a point is reached wherein the foaming to which I have referred occurs, or is about to take lace. At this oint, airis admitted at suitrhle points, pre erably' near the base of the concentrator andin sufficient quantities to insure thoroughagitation of the acid and to supply suflicient oxygen to foster and promote relatively rapid oxidation of the various organic compounds and impurities. This quantity of air, however, is maintained sufficiently low as to leave a slightvacuum in the concentrator, so that the decomposition operation is carried out directly within the concentrator under a partial vacuum. A jet condenser is associated with the concentrator to remove the resulting obnoxious fumes, and

they are disposed of by absorption in the 9 concentration of the acid is proceeded with mies in time, apparatus and; heat, it speeds up production and gives a highly SZItISfEQtOIy;

product. Furthermore, the obnoxious fumes and vapors are atall times precluded from exit to, the atmosphere. This constitutes an important feature "of th s invention.

' 2 Features of theinvention, other than those specified, will be appare nt from the herein-. after detailed description and claims,'when read in conjunction with the; accompanying drawing.

In the accompanying drawing, have shown one form of apparatus for practising the present invention, but this apparatus is to be understood as illustrative, only, and

not as defining the limits of the invention.

s In the drawing, 1 designates a vacuum con-f centrator of any suitable Qkind, shown as embodying an outer shell 2 with anappropriate liningwhich may conveniently be of lead.

I 1 The concentrator is provided at'its bottom}: with a sump 3 havinga wash outvalve 1."

A pipe 5 communicating with the base of the sump hastwo branches 6 and 7 which are s respectively" valved at 8 and '9. The branch ing coils 10 of such number and sizeas are required to properly treat the material, These coils are" f edthrough'pipes 11 from" i an exteriorhefaden 12to which the heating medium, such as steam, is supplied through a'valved inlet, 13. The ,condensate is discharged from thecoilsthrough pipes 14. The

top of the concentrator is connectedby a conduit 15to-a jet condenser16to which water b-is-supplied through a pipe 17, while afpipe Vflow waste vat.

18 leads from the condenser to, e. g., an overf Particular attention is called to the; fact :that the lower portion of the concentrator is embraced header 19 fed from an air line 20 valved at 21.; From this header 19a number of pipes 22 lead through the wall of the concentrator into'the interior thereof and ratus- -shown, a pipe 22 leads to the' 'interior ,Jand directly below eachcoil, so" that when air isintroduced, isdirected upwardly Qthrough the corresponding coil; v,This isfthe prefe ed-rem of apparatus although I wish,

i the acidjust below the bjoilingl'point.

outlets with any suitable location Without departing from this invention.

In carrying out the process of this invention, the sludge acid to be concentrated is fed into'the concentrator through the pipe 6 to about the level indicated by the line 23, so as to submerge the coils 10. All of the valves 8, 9 and 13 being closed, the valve 13 is opened to admit steam to the coils 10; Steam of suitable pressure is now introduced for the pur pose ofheatmg the'sludge acid and concentrating the same to a point where the density reachesabout 569 or 1B.-j During this time, the jet condenser functions to produce a suiiiciently high vacuum to reduce the boil- .ing point of the sludge acid to limits wherein boiling will occur at approximately 240 de- .giees tOhQGO degrees Fl *Thefumes and vapors evolved during the concentrationiopcration as stated pass outwardly throughlthe pipe 15 into'condenser 16 and are disposed of through the pipe 18.

"By the time that the acid is concentrated toabout 56 or.60 Be, decomposition of certain organic compounds, such as thesuL- phonates, is found-will cOmmence-andpro ducea violent gas evolution with resultlng foaming; :lh'en this stage. of the process is reached,,the valve 21 is opened to admit air into theheader 19 an'd this air .passesthrough .the several pipes 22 into "theinteriorlo fthe concentrator andnear the base thereof. As it is discharged from the nozzles, it passes lupwa' rdly through'the body of sludge acid contained in the concentrator producing a I marked agitation of the acid to thereby 6 is the sludge ac'id'inlet ahd the branch 7 istheoutlet e Positioned within the apparatus are heat-' 18 to be disposed otby absorption by :the

water entering the condenser. During the passage of air. through the charge n the concentrator, as stated, a part al vacuum is mam- -tai'ned in the concentrator byproperly regu;

lating the supply of air, sothat it will not be fed-in such quantities as to destroy the partialvacuum'. Injotherwords, the feed of air is such that a'slight vacuum is maintained inside ofrthe concentrator so that the fumesland air are absorbed in the water jet condenser and do not escape into the. air.

The feed of air is continued through asuf- .ficientp'eriod to decompose all the obnoxious compounds in the acid that can bethus' dis posed of. From two to four hours is generally suflicientto accomplish this result and during this period the coils are supplied with steam at suitable pressure in order to keep Atterthesaid obnoxiouscompounds have been decomposed as stated, the valve 21 is closed, the vacuum within the concentrator is :againraised to lowerthe boiling point as understoodigthat zuse'ganynumber ojf lstat'edf and thereupon steam is mast tis,

coils at a pressure of say 50 to 100 pounds, so as to promote a rapid resumption of coneentration of the acid until such acid reaches a density of approximately 6566 B.

After the acid has been concentrated to the desired density, the valve 13 is closed, the concentrator is vented as by a vent valve 24 and the valve 9 opened to permit the acid to be withdrawn and fed by gravity or through an appropriate pump to a suitable settling tank Where the carbonaceous matter still retained in the acid may be removed.

It will thus be apparent that according to the present invention, the sludge acid after being fed to the concentrator remains therein from the commencement of concentration until the completion thereof. No transfer of the acid is required, and it does not have to be removed and treated by extraneous or collateral processes after a partial concentra tion as heretofore. The complete concentration of the acid is accomplished from start to finish within the concentrator. This means not only a very pronounced saving in initial installation of apparatus, but also effects pronounced savings in the cost of operation due to economies in handling and the absence of heat losses. In practice, the process of this invention has proven highly economical and thoroughly eliicient.

It is characteristic of this invention that the process may be commercially carried out without polution of the atmosphere by resulting obnoxious gases, vapors and odors. These foul smelling and poisonous products of the operation are precluded from escaping into the atmosphere and are efficiently disposed of by absorption. The process is thus devoid of those objections which are unavoidable under prior practice. Furthermore. the workmen are not subjected to the health hazards to which I have hereinbeforereferred as attendant upon all prior processes of this general character.

The apparatus which I have shown has given thoroughly satisfactory results when operated as stated. I wish it understood, however, that the invention is not limited to this particular apparatus, but that the process of this invention. is fully commensurate with the appended claims.

I wish to point out that the entire concentration and decomposition operations are not only carried on within the concentrator as described, but that these operations occur in the sequence stated under partial vacuum. In other words. the process is in its nature continuous, the heating of the acid continues from the start of the concentration, during preliminary concentration, then through the decomposition period, and on through the final concentration period without cessation. The partial vacuum is similarly maintained although it is lower during, the decomposition period than during the concentration periods for obvious reasons. Thus the heatmg and partial vacuum may be said to be concurrent and continuous. Superior results in the reclamation of sludge acid are accomplished by this process. The heat is maintained suiiiciently low to preclude burning of organic matter contained in the acid and thus discoloration does not occur.

Having thusfully described the invention, what I claim as new and desire to secure by Letters Patent Iisz 1 1. The. process of reclaiming sludge acid in petroleum refining, which consists in partially concentrating the sludge acid in a suitable concentrator under a partial vacuum, then passing air through the acid in the con centrator in sufiicient quantities to oxidize undesirable organic compoundswhile maintaining a partial vacuum inthe concentrator, and thereafter resuming the concentration of said acid under a partial vacuum in the concentrator until it reaches a desired density.

2. The process of reclaiming sludge acid in petroleum refining, which consists in partially concentrating the sludge acid in a suitable concentrator, then passing air through the acid in the concentrator in suflicient quantities to oxidize undesirable organic compounds and thereafter resuming the concentration of said acid in the concentrator until it reaches a desired density, and maintaining an uninterrupted partial vacuum within the concentrator throughout the period of treatment. 4

3. The process of reclaiming sludge acid in petroleum refining, which consists in partially concentrating the sludge acid in a suitable concentrator While excluding air, then passing air through the acid in the concentrator in suflicient quantities to oxidize undesirable organic compounds, and thereafter resuming the concentration of said acid in the concentrator while excluding air and until the acid reaches the desired density.

4. The process of reclaiming sludge acid which consists in placing it in a suitable container, then partially concentrating the sludge acid by boiling it, then decomposing impurities in the sludge acid by passing air therethrough, while maintaining the sludge acid at approximately its boiling point, and thereafter resuming the concentration of the acid by further boiling, and maintaining the sludge acid under an uninterrupted partial vacuum in the same container throughout such process.

5. The process of reclaiming sludge acid which consists in establishing a pool of sludge acid, then boiling the same under partial vacuum to partially concentrate the acid, then oxidizing the impurities in such pool, under partial vacuum, thereafter resuming the concentration of the acid in said pool under partial vacuum until the acid reaches the desired l a'density, zind: finally With'drz wihg'the piod'uct to' dissipate said pool- 6; Thexpr'ocess of i'claiming wsludge which consists in establishing a pool of sludge a-cid-Wvithin a closed COIltiLiIlGlfthIl b'qiling x'bhe acid under partial vacuum w-ithin the con i tain'er, to partially concentrate the acid, then oxidizingthefimpurities in'said p001 Within =:the containeruhder a partial Vacuum, the1'e- I afterrssummg'che concentrationofthe ac d l s in the pool under partlal vacuumuntll the acid rea chesthe desired density, picluding 131186503138}OfObDOXlOLIS gases; and vapors Fifi-0111 the vessel during th'eperi'ods-of partial: f

15::c0ncentrati0n, oxidation and-final'concentra- 1 tion, and r finally Withdrawing the product l jfi'om thesco'ntainer to dissipate the pool.

fiiIn testimony iwhereof I OTTO MANTIIUS. v 

